Dust collecting device and impact tool

ABSTRACT

A dust collection device, that collects dust particles generated by an impact tool, has a feature that enables the attachment of the device to the impact tool, which is not provided with an attachment section for the device. The dust collection device has a tool body and an auxiliary handle, attached removably to the tool body, and is attached to an electric hammer that, in the lengthwise direction, linearly operates a tool bit mounted to the tip region of the tool body, and collects dust generated by the electric hammer. The dust collection device has: a dust collection unit that has a dust intake port at the tip; a dust collection hose, connected to the dust collection unit, for transferring dust to the downstream side; and a hose-holding unit that holds the dust collection hose. The hose-holding unit can be attached to and removed from the auxiliary handle.

FIELD OF THE INVENTION

The invention relates to a dust collecting device for collecting dustgenerated by an impact tool, and an impact tool having the dustcollecting device.

BACKGROUND OF THE INVENTION

In an impact tool which performs a hammering operation or a hammer drilloperation by a tool bit on a workpiece such as concrete, dust isgenerated during operation. Therefore, some conventional impact toolsare provided with a dust collecting device for collecting dust generatedduring operation. For example, Japanese non-examined laid-open PatentPublication No, 2007-303271 discloses a dust collecting device having acylindrical hood which is arranged to surround a tool bit. In this dustcollecting device, dust generated by operation is sucked up through afront end opening of the hood and collected via a dust collecting hose.

The above-described known impact tool has a mounting part for mounting adust collecting device on its tool body side. Therefore, the dustcollecting device cannot be attached to an impact tool having nomounting part for mounting the dust collecting device.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention

It is, accordingly, an object of the present invention to provide atechnique for attaching a dust collecting device to an impact toolhaving no mounting part for the dust collecting device, in the dustcollecting device for collecting dust generated by the impact tool.

Means for Solving the Problem

In order to solve the above-described problem, in a preferred embodimentaccording to the present invention, a dust collecting device is providedwhich is attached to an impact tool and collects dust generated by theimpact tool. The impact tool includes a tool body and an auxiliaryhandle removably mounted to the tool body, and in the impact tool, atool bit coupled to a front end region of the tool body is caused torectilinearly move in an axial direction of the tool bit. The dustcollecting device includes a dust collecting part having a dust suctionport at its front end, a dust collecting hose which is connected to thedust collecting part and through which dust is transferred downstream,and a hose holding part for holding the dust collecting hose. Further,the hose holding part can be mounted to and removed from the auxiliaryhandle. The manner in which “the hose holding part can be mounted to andremoved from the auxiliary handle” in this invention suitably includesthe manner in which the hose holding part can be mounted to and removedfrom the tool body together with the auxiliary handle when the auxiliaryhandle is mounted to and removed from the tool body, and the manner inwhich the hose holding part can be mounted to and removed from theauxiliary handle mounted to the tool body.

According to this invention, the dust collecting device can be attachedto the impact tool via the auxiliary handle. Therefore, the dustcollecting device can be attached to an existing impact tool having nomounting part for the dust collecting device. Further, the impact toolis not provided as a special tool having a dust collecting device.

According to a further embodiment of this invention, the auxiliaryhandle includes a ring-like mounting part which can hold the tool bodyfrom outside, a base formed on the mounting part, a rod-like grip to beheld by a user, and an arm extending from the grip in a directiontransverse to a longitudinal direction of the grip and having anextending end. The base and the extending end are arranged in parallelto the longitudinal direction of the grip and clamped by using a boltextending therethrough and a nut threadingly engaged with the bolt, sothat the mounting part holds the tool body. Further, the hose holdingpart is mounted to the tool body together with the auxiliary handle bythe clamping with the bolt and the nut. The manner in which “the hoseholding part is mounted to the tool body together with the auxiliaryhandle by clamping using the bolt and the nut” in this inventiontypically refers to the manner in which part of the hose holding part isheld between two members, such as between a head of the bolt and thearm, between the arm and the base, and between a pair of bases if thebase is provided in a pair.

According to this invention, the hose holding part can be mounted byutilizing the bolt and the nut provided as means for mounting theauxiliary handle to the tool body, so that the dust collecting devicecan be attached to the impact tool in a rational manner.

According to a further embodiment of this invention, the auxiliaryhandle includes an elongate grip, and a plurality of opposed armsextending from the grip in a direction transverse to a longitudinaldirection of the grip. Further, the hose holding part is disposedbetween the opposed arms and includes a telescopic mounting member whichcan extend and retract in a direction transverse to the extendingdirection of the arms, and the mounting member is secured to the armsunder tension by a biasing force acting thereon in its extendingdirection so that the hose holding part is mounted to the auxiliaryhandle.

According to this invention, with the construction in which the hoseholding part is mounted to the auxiliary handle by securing the mountingmember between the opposed arms under tension, the hose holding part canbe easily mounted and removed with the auxiliary handle left mounted tothe tool body.

According to a different embodiment of this invention, a dust collectingdevice is attached to an impact tool and collects dust generated by theimpact tool in which a tool bit coupled to a front end region of thetool body is caused to rectilinearly move in an axial direction of thetool bit. The dust collecting device includes a dust collecting parthaving a dust suction port through which dust is sucked up, a dustcollecting hose which is connected to the dust collecting part andthrough which dust is transferred downstream, and a hose holding partfor holding the dust collecting hose. Further, the hose holding part ismounted to the tool body by a wrapping member which is detachablywrapped around the tool body. The “wrapping member” in this inventionsuitably includes a flexible band-like member such as a belt, a band anda tape and a flexible string-like member such as a rope and a ballchain.

According to this invention, by wrapping the wrapping member around thetool body, the hose holder can be mounted to the tool body, so that thedust collecting device can be attached to the impact tool. Therefore,the dust collecting device can be easily attached to an existing impacttool having no mounting part for the dust collecting device. Further,the impact tool is not provided as a special tool having a dustcollecting device.

According to a further embodiment of this invention, an impact toolhaving the dust collecting device as defined in any one of claims 1 to 4is provided. Thus, the impact tool can be provided with the dustcollecting device which can be easily attached to an existing impacttool having no mounting part for the dust collecting device.

Effect of the Invention

According to this invention, in a dust collecting device for collectingdust generated by an impact tool, a technique is provided for attachinga dust collecting device to an existing impact tool having no mountingpart for the dust collecting device.

Other objects, features and advantages of the present invention will bereadily understood after reading the following detailed descriptiontogether with the accompanying drawings and the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an external view showing an entire electric hammer with a dustcollecting device according to a first embodiment of the presentinvention.

FIG. 2 is a sectional view showing the entire structure of the dustcollecting device.

FIG. 3 is a front view showing the configuration of a front end of adust collecting hood.

FIG. 4 is a partially sectional view showing the entire structure of aside handle.

FIG. 5 is a view in the direction of arrow A in FIG. 4.

FIG. 6 is a partially sectional view showing a structure of mounting thedust collecting device or particularly a hose holder to the side handle.

FIG. 7 is a view in the direction of arrow B in FIG. 6.

FIG. 8 is a front view showing a modification of a hose holder forholding a dust collecting hose, when the dust collecting hose is lockedagainst movement.

FIG. 9 is a front view also showing the modification of the hose holderwhen the dust collecting hose is unlocked.

FIG. 10 is a view in the direction of arrow C in FIG. 8.

FIG. 11 is a partially sectional view showing a modification of astructure of mounting the dust collecting device or particularly thehose holder to the side handle.

FIG. 12 is a sectional view taken along line D-D in FIG. 11 and showingthe hose holder mounted to the side handle.

FIG. 13 is also a sectional view taken along line D-D in FIG. 11 andshowing the hose holder in the process of mounting (removing) the sidehandle.

FIG. 14 is a partially sectional view showing another modification of astructure of mounting the dust collecting device or particularly thehose holder to the side handle.

FIG. 15 is a sectional view taken along line E-E in FIG. 14.

FIG. 16 is a top view showing the hose holder.

FIG. 17 is a partially sectional view showing a further modification ofa structure of mounting the dust collecting device or particularly thehose holder to the side handle.

FIG. 18 is a view in the direction of arrow F in FIG. 17.

FIG. 19 is a partially sectional view showing a mounting member for thehose holder.

FIG. 20 is a partially sectional view showing a further modification ofa structure of mounting the dust collecting device or particularly thehose holder to the side handle.

FIG. 21 is a front view illustrating a structure of mounting the dustcollecting device or particularly the hose holder to the body of theelectric hammer, according to a second embodiment of the presentinvention.

FIG. 22 is a side view thereof.

REPRESENTATIVE EMBODIMENT OF THE INVENTION

Each of the additional features and method steps disclosed above andbelow may be utilized separately or in conjunction with other featuresand method steps to manufacture and use improved dust collecting devicesand impact tools and methods for using them and devices utilizedtherein. Representative examples of the present invention, whichexamples utilized many of these additional features and method steps inconjunction, is now described in detail with reference to the drawings.This detailed description is merely intended to teach a person skilledin the art further details for practicing preferred aspects of thepresent teachings and is not intended to limit the scope of theinvention. Only the claims define the scope of the claimed invention.Therefore, combinations of features and steps disclosed within thefollowing detailed description may not be necessary to practice theinvention in the broadest sense, and are instead taught merely toparticularly describe some representative examples of the invention,which detailed description will now be given with reference to theaccompanying drawings.

First Embodiment of the Invention

A dust collecting device according to a first embodiment of the presentinvention is now described with reference to FIGS. 1 to 7. Thisembodiment is explained as being applied to an electric hammer as arepresentative example of an impact tool. FIG. 1 shows an electrichammer 101 having an auxiliary handle in the form of a side handle 110mounted thereon and a dust collecting device 140 attached to the sidehandle 110. The construction of the electric hammer 101 is now brieflyexplained with reference to FIG. 1. The hammer 101 mainly includes abody 103 that forms an outer shell of the hammer 101, an elongate hammerbit 119 detachably coupled to the front end region (on the left side asviewed in FIG. 1) of the body 103 via a tool holder (not shown), and amain handle in the form of a handgrip 109 connected to the body 103 onthe side opposite to the hammer bit 119 and designed to be held by auser. The body 103 and the hammer bit 119 are features that correspondto the “tool body” and the “tool bit”, respectively, according to thepresent invention. The hammer bit 119 is held by the tool holder via achuck 108 such that it is allowed to reciprocate with respect to thetool holder in its axial direction and prevented from rotating withrespect to the tool holder in its circumferential direction. For thesake of convenience of explanation, in the hammer 101, the side of thehammer bit 119 is taken as the front and the side of the main handle 109as the rear.

The body 103 mainly includes a housing 105 and a generally cylindricalbarrel 107 connected to the front of the housing 105. The body 103houses a driving motor, a motion converting mechanism in the form of acrank mechanism which converts rotation of the driving motor into linearmotion, and a striking mechanism which is driven by the crank mechanismand includes a striker (striking element) for striking the hammer bit119 in the axial direction and an impact bolt (intermediate element) fortransmitting the striking movement of the striker to the hammer bit 119.

In the hammer 101 constructed as described above, when the driving motoris driven, a striking force is applied to the hammer bit 119 in theaxial direction from the crank mechanism via the striking mechanism.Thus, the hammer bit 119 performs an operation (chipping operation) on aworkpiece (concrete) by a hammering movement in the axial direction.

The auxiliary handle in the form of the side handle 110 to which thedust collecting device 140 is attached is now explained with referenceto FIGS. 4 and 5. The side handle 110 is detachably mounted onto thebarrel 107 of the hammer 101. The side handle 110 mainly includes amounting ring 111 which is mounted onto the generally cylindrical barrel107 by holding the outer circumferential surface of the barrel 107 fromthe outside, a grip 121 connected to the mounting ring 111 and designedto be held by a user, and a fastening means which includes a throughbolt 131 and a fastening knob 135 with a nut 133 and serves to clamp andloosen the mounting ring 111.

The mounting ring 111 includes a pair of upper and lower generallysemi-circular arc ring components 113. The pair ring components 113 arerotatably connected at one end with respect to each other via a shaft117 which extends parallel to the longitudinal direction of the barrel107. An outwardly protruding base 115 is formed on the other free end ofeach of the ring components 113.

The grip 121 has a rod-like shape having a generally circular sectionand has upper and lower arms 123 which extend parallel to each otherfrom the both ends of the grip 121 in the longitudinal direction (thevertical direction as viewed in FIG. 4) toward the mounting ring 111.The bases 115 of the mounting ring 111 are disposed between extendingend portions 125 of the upper and lower arms 123 via ring-like cams 137.The through bolt 131 is loosely inserted in the vertical directionthrough holes formed in the extending end portions 125, the cams 137 andthe bases 115. The through bolt 131 has a hexagonal head 131 a on oneend, and the head 131 a engages with an upper surface (bottom of acounterbore) of the extending end portion 125 of the upper arm 123. Theother end of the through bolt 131 protrudes a predetermined distancefrom the extending end portion 125 of the lower arm 123. The nut 133 ofthe fastening knob 135 is threadingly engaged with a threaded portion ofthe through bolt 131.

In the side handle 110 constructed as described above, when the mountingring 111 is loosely fitted onto the barrel 107 and the fastening knob135 is turned in one direction (tightening direction), the upper andlower extending end portions 125 are clamped (pressed) and moved(deformed), due to elasticity of the arms 123, in a direction thatlessens a distance therebetween (toward each other) by using the throughbolt 131 and the fastening knob 135 (the nut 133). As a result, thebases 115 are also moved toward each other via the upper and lower cams137 in a direction that lessens the ring diameter of the ring components113. Thus, the mounting ring 111 is clamped onto the barrel 107.

When the fastening knob 135 is turned in the other direction (looseningdirection), the upper and lower extending end portions 125 and the bases115 clamped by the through bolt 131 and the fastening knob 135 arereleased and return to their initial position in which they are not yetclamped, so that the mounting ring 111 is unclamped from the barrel 107.In this state, the side handle 110 can be removed from the barrel 107.

The dust collecting device 140 is now explained with reference to FIGS.1 to 3. The dust collecting device 140 is attached to the side handle110 and serves to suck up and collect dust generated during operation ona workpiece. The dust collecting device 140 according to this embodimentmainly includes a resin or rubber dust collecting hood 141 forcollecting dust, a dust collecting hose 146 for transferring dustdownstream from the dust collecting hood 141, and a hose holder 147 forholding the dust collecting hose 146. The dust collecting hood 141, thedust collecting hose 146 and the hose holder 147 are features thatcorrespond to the “dust collecting part”, the “dust transfer part” andthe “hose holding part”, respectively, according to the presentinvention.

As shown in FIGS. 2 and 3, the dust collecting hood 141 is a generallycup-like member (generally cylindrical member with a bottom) which isarranged to surround the hammer bit 119 entirely around its axis with apredetermined clearance in the radial direction and has an internalspace 141 b with an open front end formed as a dust suction port 141 a.On its bottom (on the side opposite from the dust suction port 141 a),the dust collecting hood 141 has a through hole 141 c extending in theaxial direction of the hammer bit and formed for mounting a cylindricalsliding member 143 therein, and a hose connecting part 144 formedadjacent to the through hole 141 c.

The cylindrical sliding member 143 is a guiding member for the dustcollecting hood 141 and has a bore which is slidably fitted onto a shank119 b of the hammer bit 119. The cylindrical sliding member 143 isdetachably fitted in the through hole 141 c of the dust collecting hood141. The dust suction port 141 a of the dust collecting hood 141 isdisposed at a predetermined distance away from a bit tip 119 a of thehammer bit 119 by fitting the cylindrical sliding member 143 onto thehammer bit 119 from the front. The bore inner wall surface of thecylindrical sliding member 143 is slidably engaged with the outersurface of the shank of the hammer bit 119. Thus, the dust collectinghood 141 is held on the shank 119 b of the hammer bit 119, while beingallowed to move in the axial direction with respect to the hammer bit119 via the cylindrical sliding member 143.

The hose connecting part 144 has an open front end formed as a dustinlet into the internal space 141 b of the dust collecting hood 141. Thehose connecting part 144 extends rearward to a predetermined lengthalong the outer contour (tapered cylindrical shape) of the chuck 108.The hose connecting part 144 has an open rear end formed as a dustoutlet, and the dust collecting hose 146 is detachably inserted in andconnected to the dust outlet. Further, a partition 145 is formed in afront end region of the hose connecting part 144 and serves to partitiona passage of the hose connecting part 144 into several parts. The hoseconnecting part 144 is partitioned into passages 144 a by the partition145 such that the flow passage sectional area of each passage 144 a issmaller than the minimum flow passage sectional area of the dustcollecting hose 146. With this construction, a large piece of dust(chip) is blocked by the partition 145 and prevented from entering thedust collecting hose 146, so that clogging of the hose can be avoided.

As shown in FIG. 3, the dust collecting hood 141 has a generallyelliptical shape in front view (when viewed from the bit tip of thehammer bit 119). Further, as shown in FIG. 2, the front end region (thedust suction port 141 a side) of the dust collecting hood 141 includes aregion on a connecting part side for connection with the dust collectinghose 146 and a region on the opposite side of the hammer bit 119 fromthe connecting part side. The front end region of the dust collectinghood 141 is inclined such that it extends away from the bit tip 119 a ofthe hammer bit 119 on the hose connecting part 144 side, while extendingtoward the bit tip on the opposite side. Specifically, the front endregion of the dust collecting hood 141 has a circumferential shapeinclined with respect to the axial direction of the hammer bit 119 suchthat the region on the hose connecting part 144 side extends away fromthe bit tip 119 a. With this configuration, visibility of the bit tip119 a (a work area of the workpiece) can be improved when it is viewedover the hose connecting part 144, and dust sucked up into the dustcollecting hood 141 can be smoothly led into the hose connecting part144.

The dust collecting hose 146 is a tubular member made of rubber or resinand having a bellows-like part 146 a formed at least in part of the dustcollecting hose 146. The dust collecting hose 146 is connected to thedust collecting hood 141 by inserting one (front) end of the dustcollecting hose 146 into the dust outlet of the hose connecting part144. The dust collecting hose 146 extends along the body 103 of thehammer 101 generally in the axial direction of the hammer bit 119 and isheld on the barrel 107 via the side handle 110 by the hose holder 147.Further, the dust collecting hose 146 is connected to a dust collector(not shown) at least during operation. In this manner, the dustcollecting device 140 of this embodiment is constructed to be held onthe hammer 101 at two points in the longitudinal direction such that thedust collecting hose 146 is held on the body 103 and the dust collectinghood 141 is held on the hammer bit 119. Further, in this embodiment, thedust collecting hose 146 is connected to a dust collector formedseparately from the hammer 101, but it may be connected otherwise. Forexample, if the hammer 101 has a suction device including a motor and amotor-driven dust collecting fan, or if the dust collecting deviceitself has a suction device including a motor and a motor-driven dustcollecting fan, the dust collecting hose 146 may be connected to thesuction device.

As shown in FIGS. 6 and 7, the hose holder 147 has a hose holder body148 for holding the dust collecting hose 146 and a plate-like mountingbase 149 extending from the hose holder body 148. The hose holder body148 is a generally circular ring-like member having a hoseattachment/removal opening 148 a. A plurality of circumferentiallyextending rib-like projections 148 b are formed on an innercircumferential surface of the hose holder body 148 and can engage withvalleys of the bellows-like part 146 a of the dust collecting hose 146.The opening width of the hose attachment/removal opening 148 a in thecircumferential direction is slightly smaller than the hose diameter.Therefore, in order to attach and remove the hose with respect to thehose holder body 148 through the opening 148 a, the bellows-like part146 a is deformed into a generally elliptical form. The dust collectinghose 146 held by the hose holder body 148 is locked against axialmovement by engagement between the projections 148 a and the valleys ofthe bellows-like part 146 a.

The mounting base 149 is inserted between a head 131 a of the throughbolt 131 and the upper arm 123 of the grip 121 in the side handle 110and fastened to the side handle 110. The mounting base 149 can beremoved from the side handle 110 when the through bolt 131 is loosened.For this purpose, as shown in FIGS. 6 and 7, the mounting base 149 has anotch 151 and a recessed engagement part 152. The notch 151 is generallyU-shaped in planar view and can be fitted onto the through bolt 131 froma radial direction. The recessed engagement part 152 is formed along aperipheral edge of an upper surface of the notch 151, engaged with thehead 131 a of the through bolt 131 fitted in the notch 151 and lockedagainst rotation relative to the head 131 a. Therefore, when the throughbolt 131 is loosened, the hose holder 147 can be turned about 360degrees around the through bolt 131, so that its position can beadjusted around the bolt axis. When the through bolt 131 is tightened byturning the fastening knob 135 after the hose holder 147 is set in apredetermined position around the through bolt 131, the through bolt 131engaged at the head 131 a with the recessed engagement part 152 andlocked against rotation is moved toward the fastening knob 135. In thismanner, the mounting base 149 is fastened to the side handle 110 betweenthe head 131 a of the through bolt 131 and the upper arm 123.

The dust collecting device 140 according to this embodiment isconstructed as described above. When a dust collector is driven and thehammer 101 is driven to perform a chipping operation on a workpiece bylinear hammering movement of the hammer bit 119, the dust collectingdevice 140 can collect dust generated during the operation.Specifically, dust generated by the hammer 101 is sucked up into thedust collecting hood 141 through the dust suction port 141 a andcollected in the dust collector via the hose connecting part 144 of thedust collecting hood 141 and the dust collecting hose 146.

In chipping operation, hammer bits 119 of different lengths are usedaccording to the operation conditions. In consideration of this, in thisembodiment, the position of the front end of the dust collecting hood141 (the position of the dust suction port 141 a) can be adjusted withrespect to the hammer bit 119 by changing the position of the hoseholder 147 for holding the dust collecting hose 146. Thus, the dustsuction port 141 a can be positioned at an adequate distance from thebit tip of the hammer bit 119 to be used. As a result, such a problemthat the dust collecting efficiency is reduced by increase of thedistance between the dust suction port 141 a and a dust generation areacan be eliminated. According to this embodiment, the hammer bits 119having different lengths can be accommodated without reducing the dustcollecting ability, and a plurality of dust collecting hoods 141 are notneeded.

Further, the hammer bits 119 are available in several types varying inlength and in several types varying in the diameter of the shanks 119 b.In consideration of this, in this embodiment, the cylindrical slidingmember 143 is detachably fitted in the through hole 141 c of the dustcollecting hood 141. Further, a plurality of cylindrical sliding members143 having bores of different diameters are provided to accommodate aplurality of hammer bits 119 having the shanks 119 b of differentdiameters. Thus, the cylindrical sliding members 143 can be replaced andmounted in the through hole 141 c of the dust collecting hood 141 inorder to accommodate the hammer bits 119 having the shanks 119 b ofdifferent diameters.

Further, in this embodiment, the dust collecting hose 146 can beattached to and removed from the hose holder body 148 through the hoseattachment/removal opening 148 a, and the dust collecting hose 146 islocked against axial movement and held by engagement between therib-like projections 148 b of the hose holder body 148 and the valleysof the bellows-like part 146 a of the dust collecting hose 146. Withthis construction, the front end position of the dust collecting hood141 can be easily adjusted by changing the position of engagement of thebellows-like part 146 a with respect to the projections 148 a whenattaching the dust collecting hose 146. Further, with the constructionin which the dust collecting hose 146 is locked against axial movementby engagement between the rib-like projections 148 a and the valleys ofthe bellows-like part 146 a, the dust collecting hood 141 can beprevented from being displaced by vibration during chipping operation sothat it can be reliably and securely held in position.

Further, in this embodiment, the sleeve-like cylindrical sliding member143 is provided on part of the dust collecting hood 141 and slidablyfitted onto the shank 119 b of the hammer bit 119, and the dustcollecting hood 141 is directly guided by the shank 119 b of the hammerbit 119. With this construction, the dust collecting hood 141 can beheld with stability. Further, by provision of the holding stability, thedust collecting hood 141 can be placed closer to an area of dustgeneration or the tip of the hammer bit 119, so that the dust collectingefficiency can be improved.

Further, in this embodiment, the front end region of the dust collectinghood 141 is inclined with respect to the axis of the hammer bit 119.Therefore, when a chipping operation is performed, for example, on avertical wall, part (the dust collecting hose connection side) of thecircumferential region of the dust collecting hood 141 which extendsaway from the bit tip 119 a is set to be positioned in the line ofsight, or between a user's eye and a work area of the workpiece duringoperation, so that visibility of the work area of the workpiece can beimproved when the work area is viewed over the dust collecting hood 141.Further, part of the circumferential region of the dust collecting hood141 which extends toward the bit tip 119 a is placed below the hammerbit 119. With this construction, the dust suction port 141 a can moreeasily catch chips which are scattered during chipping operation.

Further, in this embodiment, the dust collecting hood 141 has agenerally cup-like shape and is arranged to surround the shank 119 bentirely around its axis at a distance away from the bit tip 119 a ofthe hammer bit 119. With this construction, the dust collecting hood 141can be made smaller, and visibility of the work area can be improved.

Further, in this embodiment, the mounting base 149 of the hose holder147 can be inserted between the head 131 a of the through bolt 131 andthe upper arm 123 of the grip 121 in the side handle 110 and clamped tothe side handle 110. The mounting base 149 can be removed from the sidehandle 110 by loosening the through bolt 131. Specifically, according tothis embodiment, when the side handle 110 is mounted to the body 103,the hose holder 147 for holding the dust collecting hose 146 of the dustcollecting device 140 can be mounted to the body 103 of the electrichammer 101 together with the side handle 110. Therefore, even if thehammer 101 is not provided with a mounting part for the dust collectingdevice 140, the dust collecting device 140 can be attached to the hammer101. Further, with the construction in which the hose holder 147 isclamped by utilizing the through bolt 131 and the nut 133 provided asmeans for mounting the side handle 110 to the body 103, the dustcollecting device 140 can be easily attached, and not only the body 103but the side handle 110 does not need its structural change for suchmounting.

A modification in relation to a structure of holding the dust collectinghose 146 of the dust collecting device 140 is now described withreference to FIGS. 8 to 10. This modification is a modification to thehose holder 147, which is described in the first embodiment, for holdingthe dust collecting hose 146 of the dust collecting device 140. Theentire construction of the dust collecting device 140 other than thehose holder is the same as in the first embodiment.

A hose holder 161 of this modification mainly includes an annular hoseholder body 162 which serves to hold the dust collecting hose 146 andthrough which the dust collecting hose 146 can be inserted, a plate-likemounting base 163 extending from the hose holder body 162, and asemicircular locking member 164 for locking the dust collecting hose 146to the hose holder body 162. The hose holder 161 is a feature thatcorresponds to the “hose holding part” according to this invention.

The hose holder body 162 is a circular ring-like member having an innerdiameter slightly larger than the outer diameter of the bellows-likepart 146 a of the dust collecting hose 146. The hose holder body 162 hasan opening 162 a (see FIG. 10) formed in the middle in its axialdirection and extending over a predetermined area (of about 180 degrees)in the circumferential direction. The locking member 164 has a generallysemi-circular arc shape having about the same radius of curvature as theinner diameter of the hose holder body 162, and is disposed in theopening 162 a of the hose holder body 162. One end of the locking member164 is rotatably connected to the hose holder body 162 by a pin 165. Atthe other end, the locking member 164 has a protruding end 164 aprotruding radially outward of the hose holder body 162. The protrudingend 164 a faces an upper surface of the mounting base 163. One or morelocking projections 164 h are formed on the inner surface of the lockingmember 164 and protrude radially inward. The locking projections 164 bare engaged with the valleys of the bellows-like part 146 a of the dustcollecting hose 146 so that the dust collecting hose 146 is lockedagainst axial movement with respect to the hose holder body 162. Thisstate is shown in FIG. 8.

A compression coil spring 166 is disposed as a biasing member betweenthe mounting base 163 and the protruding end 164 a which face eachother. Thus, the locking member 164 is biased to turn radially inwardsuch that the locking projections 164 b are engaged with the valleys ofthe bellows-like part 146 a of the dust collecting hose 146. Therefore,the locking projections 164 b and the valleys of the bellows-like part146 a are held in engagement and the dust collecting hose 146 is lockedagainst axial movement. The locking member 164 has a stopper 164 c fordefining the limit to which the locking member 164 can be turnedradially inward by the compression coil spring 166. The stopper 164 c isformed as a projection extending in the axial direction on the outercircumferential surface of the locking member 164. When the lockingmember 164 is turned radially inward, the stopper 164 c comes intocontact with the outer surface of the hose holder body 162 and preventsthe locking member 164 from being further turned.

Further, the protruding end 164 a of the locking member 164 forms anoperation knob. When the protruding end 164 a is pressed against thebiasing force of the compression coil spring 166, the locking member 164is turned radially outward on the pin 165. Thus, the locking projections164 b are disengaged from the bellows-like part 146 a, so that the dustcollecting hose 146 is allowed to move in the axial direction. Thisstate is shown in FIG. 9.

According to this embodiment constructed as described above, after theprotruding end 164 a of the locking member 164 is pressed and thelocking projections 164 b are disengaged from the bellows-like part 146a of the dust collecting hose 146, the position of the front end of thedust collecting hood 141 can be adjusted with respect to the hammer bit119 by moving the dust collecting hose 146 in the axial direction. Oncethe dust collecting hood 141 is positioned, engagement between thebellows-like part 146 a and the locking projections 164 b is maintainedby the compression coil spring 166. Therefore, there exists no risk thatthe dust collecting hood 141 is unintentionally displaced due tovibration caused by the operation.

Modifications to a mounting structure for mounting the dust collectingdevice 140 to the side handle 110, or particularly to a mountingstructure for mounting the hose holder 147 are now described withreference to FIGS. 11 to 20.

First, a modification shown in FIGS. 11 to 13 is explained. In thismodification, the hose holder 147 is mounted to the side handle 110 viaa clamping mechanism 153 provided on the mounting base 149. The clampingmechanism 153 is secured to the side handle 110 by clamping the upperarm 123 of the side handle 110 from above and below. The dust collectingdevice 140 has the same construction as in the first embodiment, andonly part of the dust collecting device 140 or the hose holder 147 isshown in FIGS. 11 to 13.

The clamping mechanism 153 mainly includes a fixed clamp aim 154 and amovable clamp arm 155 which have respective clamp faces 154 a, 155 afacing each other, a clamping biasing member in the form of acompression coil spring 156 which constantly biases the movable clamparm 155 toward the fixed clamp arm 154, and an unclamping operationmember 157 for moving the movable clamp arm 155 away from the fixedclamp arm 154.

The fixed clamp arm 154 is integrally formed with the mounting base 149of the hose holder 147. As shown in FIGS. 12 and 13, the fixed clamp arm154 includes a clamp part 154 b having a lower surface with the clampface 154 a, and an arm guide part 154 c which extends downward from oneend of the clamp part 154 b and is wrapped around to the back(underside) of the clamp face 155 a of the movable clamp arm 155. Themovable clamp arm 155 is disposed below the clamp face 154 a. Themovable clamp arm 155 has a guide rod 155 b integrally formed on itsback side opposite from the clamp face 155 a, and the guide rod 155 b isslidably inserted in a guide hole of the arm guide part 154 c.

The compression coil spring 156 is disposed around the guide rod 155 bbetween the arm guide part 154 c and the movable clamp arm 155 andbiases the movable clamp arm 155 toward the fixed clamp arm 154. Theoperation member 157 is formed by a knob which is fastened to the lowerend of the guide rod 155 b by a screw 158.

The hose holder 147 is mounted to the side handle 110 by the clampingmechanism 153. Specifically, as shown in FIG. 13, the operation member157 is pulled down so that the movable clamp arm 155 is moved away fromthe fixed clamp arm 154. In this state, the upper arm 123 of the sidehandle 110 is placed between the movable clamp arm 155 and the fixedclamp arm 154 and the operation member 157 is released. Thus, as shownin FIG. 12, the movable clamp arm 155 is moved toward the fixed clamparm 154 by the biasing force of the compression coil spring 156, and thearm 123 is clamped by the clamp faces 154 a, 155 a. In this manner, thehose holder 147 can be mounted to the side handle 110.

According to this modification in which the hose holder 147 can bemounted to the side handle 110 by using the clamping mechanism 153, likein the first embodiment, the dust collecting device 140 can be attachedvia the side handle 110 to the electric hammer 101 having no mountingpart for the dust collecting device 140. Further, the hose holder 147can be mounted to and removed from the side handle 110 by simpleoperation of pulling and releasing the operation member 157. Thus,workability in attaching and removing the hose holder can be improved.

As an alternative of the construction of the clamping mechanism 153, forexample, the movable clamp arm 155 and the operation member 157 may beconnected by a feeding mechanism using a feed screw and a nut. In thiscase, the movable clamp arm 155 is rectilinearly moved by turning theoperation member 157, so that the arm 123 is clamped by the movableclamp arm 155 and the fixed clamp arm 154.

Now, a modification shown in FIGS. 14 to 16 is explained. In thismodification, the hose holder 147 is mounted by the through bolt 131between the bases 115 of the pair ring components 113 forming themounting ring 111 of the side handle 110. In the other points, theentire construction of the dust collecting device 140 is generally thesame as in the above-described first embodiment, and only part of thedust collecting device 140 or the hose holder 147 is shown in FIGS. 14to 16.

The hose holder 147 mainly includes a hose holder body 148 for holdingthe dust collecting hose 146 and a projection 185 integrally formed onthe outer surface of the hose holder body 148. The hose holder body 148is a generally circular ring-like member having a hoseattachment/removal opening 148 a. A plurality of circumferentiallyextending rib-like projections 148 b are formed on the innercircumferential surface of the hose holder body 148 and can engage withvalleys of the bellows-like part 146 a of the dust collecting hose 146.As shown in FIG. 16, the projection 185 protrudes in a radial directionof the hose holder body 148. A semicircular cylindrical part 186 isformed on the protruding end of the projection 185 and can engage withthe shank of the through bolt 131. The semicircular cylindrical part 186has an insertion opening 186 a in part in the circumferential direction.

As for the side handle 110, as shown in FIG. 14, when the mounting ring111 is clamped to the barrel 107 of the body 103, it has a predeterminedclearance (distance) between the bases 115 of the pair ring components113 which is large enough to receive the semicircular cylindrical part186 of the projection 185. Therefore, in order to mount the hose holder147 onto the through bolt 131, the insertion opening 186 a of thesemicircular cylindrical part 186 is pressed from the radial directionagainst the shank of the through bolt 131 through the clearance betweenthe bases 115, and the semicircular cylindrical part 186 is fitted ontothe shank by utilizing elastic deformation of the semicircularcylindrical part 186. Further, in order to remove the hose holder 147from the shank, the semicircular cylindrical part 186 is pulled in adirection opposite to the pressing direction.

As described above, according to this modification in which the hoseholder 147 can be mounted onto the through bolt 131 of the side handle110, like in the first embodiment, the dust collecting device 140 can beattached via the side handle 110 to the electric hammer 101 having nomounting part for the dust collecting device 140.

Further, according to this modification, when the side handle 110 ismounted by clamping the mounting ring 111 to the barrel 107, theclearance between the opposed upper and lower bases 115 is slightlylonger than the axial length of the semicircular cylindrical part 186.Therefore, the side handle 110 can be left mounted to the barrel 107while fitting and removing the semicircular cylindrical part 186 withrespect to the shank of the through bolt 131.

Further, it may be constructed such that the clearance between theopposed upper and lower bases 115 is generally equal to the axial lengthof the semicircular cylindrical part 186, and such that the projection185 is fastened between the upper and lower bases 115 when the mountingring 111 is clamped onto the barrel 107 with the through bolt 131 andthe nut 133.

Now, a modification shown in FIGS. 17 to 19 is explained. In thismodification, the hose holder 147 is mounted by utilizing the upper andlower arms 123 of the side handle 110. In the other points, the entireconstruction of the dust collecting device 140 is generally the same asin the above-described first embodiment, and only part of the dustcollecting device 140 or the hose holder 147 is shown in FIGS. 17 to 19.

As shown in FIG. 19, the hose holder 147 mainly includes a hose holderbody 148 for holding the dust collecting hose 146 and a telescopictension member 187 connected to the hose holder body 148. The tensionmember 187 is a feature that corresponds to the “mounting member”according to this invention. The hose holder body 148 is a generallycircular ring-like member having a hose attachment/removal opening 148a. A plurality of circumferentially extending rib-like projections 148 bare formed on the inner circumferential surface of the hose holder body148 and can engage with valleys of the bellows-like part 146 a of thedust collecting hose 146.

The tension member 187 includes a cylindrical first rod-like member 188,a second rod-like member 189 which is slidably inserted into the firstrod-like member 188, and a biasing member in the form of a compressioncoil spring 191 which is disposed within the first rod-like member 188and biases the second rod-like member 189 in a direction (extendingdirection) in which that the second rod-like member 189 protrudes out ofthe first rod-like member 188. Two-pronged engagement recesses 188 a,189 a are formed in the ends of the first and second rod-like members188, 189 in the extending direction and can engage with the arms 123.

In the hose holder 147 according to this modification, the tensionmember 187 can be shortened by applying external force to the first andsecond rod-like members 188, 189 inwardly toward each other against thebiasing force of the compression coil spring 191. In order to mount thehose holder 147 to the side handle 110, in this shortened state, thetension member 187 is placed between the upper and lower arms 123 andthen the external force is released, so that the tension member 187extends by the biasing force of the compression coil spring 191. At thistime, for example, the engagement recess 188 a of the first rod-likemember 188 is engaged with the lower arm 123, and the engagement recess189 a of the second rod-like member 189 is engaged with the upper arm123.

As described above, according to this modification in which the hoseholder 147 can be mounted to the side handle 110 between the upper andlower arms 123 via the tension member 187, like in the first embodiment,the dust collecting device 140 can be attached via the side handle 110to the electric hammer 101 having no mounting part for the dustcollecting device 140. Further, by provision of the mounting structureusing the tension member 187, the side handle 110 can be left mounted tothe barrel 107 while mounting and removing the hose holder 147 withrespect to the side handle 110.

Further, although, in the above-described modification, the tensionmember 187 is constructed to secure the hose holder 147 to the sidehandle 110 under tension by the biasing force of the compression coilspring 191, a threaded structure may also be used for this purpose undertension.

Now, a modification shown in FIG. 20 is explained. In this modification,the hose holder 147 is mounted to one axial end of the through bolt 131by using a mounting screw 193. In the other points, the entireconstruction of the dust collecting device 140 is generally the same asin the above-described first embodiment, and only part of the dustcollecting device 140 or the hose holder 147 is shown in FIG. 20.

Like in the first embodiment, the hose holder 147 of this modificationincludes a generally circular ring-like hose holder body 148 and aplate-like mounting base 149 extending from the hose holder body 148.The hose holder body 148 has a hose attachment/removal opening 148 a,and a plurality of rib-like projections 148 b are formed on the innercircumferential surface of the hose holder body 148 and can engage withvalleys of the bellows-like part 146 a of the dust collecting hose 146.The mounting base 149 has a through hole 149 a extending therethrough ina direction transverse to its extending direction and a boss 149 bformed coaxially with the through hole 149 a on one side (surface ofcontact with the fastening knob 135). An axially extending threaded hole131 b is formed in one end of the through bolt 131 (on the fasteningknob 135 side with the nut 133).

Therefore, in order to fasten the hose holder 147 to the side handle110, the boss 149 b of the mounting base 149 is inserted in a nutreceiving recess formed in the fastening knob 135. Then a mounting screw193 is inserted through the through hole 149 a via a sleeve 194 andthreadingly engaged with the threaded hole 131 b of the through bolt131.

As described above, according to this modification in which the hoseholder 147 is mounted to the through bolt 131 of the side handle 110 bythe mounting screw 193, like in the first embodiment, the dustcollecting device 140 can be mounted via the side handle 110 to theelectric hammer 101 having no mounting part for the dust collectingdevice 140. Further, this modification can be realized by a slightstructural change or simply by forming the screw hole 131 b in thethrough bolt 131.

Second Embodiment of the Invention

A second embodiment of the present invention relating to a structure ofmounting the dust collecting device 140 to the electric hammer 101 isnow described with reference to FIGS. 21 and 22. According to thisembodiment, a flexible band-like member 197 such as a belt, a tape and aband is used to attach the dust collecting device 140 to the body 103 ofthe hammer 101 by wrapping around the body 103. The band-like member 197is a feature that corresponds to the “wrapping member” according to thisinvention. The entire construction of the dust collecting device 140 isgenerally the same as in the above-described first embodiment, and onlypart of the dust collecting device 140 or the hose holder 147 is shownin FIGS. 21 and 22.

The hose holder 147 of the dust collecting device 140 according to thisembodiment is constructed such that the band-like member 197 is passedthrough a wide hole formed in the base of the hose holder 148.Therefore, the hose holder 147 can be fixedly mounted to the body 103 bywrapping the band-like member 197 around the body 103, specificallyaround the axis of the barrel 107. As a result, the dust collecting hose146 of the dust collecting device 140 can be held by the hose holder147. Therefore, like in the above-described first embodiment, even ifthe hammer 101 is not provided with a mounting part for the dustcollecting device 140, the dust collecting device 140 can be attached tothe hammer 101. Further, when the band-like member 197 is wrapped aroundthe barrel 107, the hose holder 147 can be set at any position aroundthe axis of the hammer bit 119. Therefore, it can be positioned to avoidthe dust collecting hose 146 from interfering with the operation.

The band-like member 197 typically has a structure of fastening by ahook and loop fastener. The means for fastening the band-like member 197however is not limited to the hook and loop fastener, but various othermethods can be appropriately used. For example, the fastening methodsinclude a method of fastening by inserting a pin through a belt hole, amethod of buckling the belt by a fastener or a so-called buckle, and amethod of fastening by looping the belt back through a rectangular ringand tightening the belt.

The band-like member 197 may be wrapped around the barrel 107 forward orrearward of the side handle 110, or it may be wrapped around themounting region for the side handle 110 provided that the side handle110 is removed.

The wrapping member is not limited to the band-like member 197, but itmay be a flexible string-like member such as a rope and a chain (e.g. aball chain formed by coupling a number of balls). Further, the wrappingmember may be formed by a pair of semicircular plates similar to themounting ring 111 of the side handle 110, or it may be formed by anelastically deformable ring member having a cut in part in thecircumferential direction.

Further, in the above-described embodiments, the electric hammer inwhich the hammer bit 119 performs only hammering movement in the axialdirection is explained as a representative example of the impact toolaccording to the present invention, but the present invention can alsobe applied to a hammer drill which can switch between hammering mode inwhich the hammer bit 119 performs hammering movement and hammer drillmode in which it performs hammering movement in the axial direction andhammer drill movement in the circumferential direction.

In view of the scope and spirit of the above-described invention, thefollowing features can be provided.

(1) “A dust collecting device that is attached to an impact tool andcollects dust generated by the impact tool which includes a tool bodyand an auxiliary handle removably mounted to the tool body and in whicha tool bit coupled to a front end region of the tool body is caused torectilinearly move in an axial direction of the tool bit, comprising:

a dust collecting part having a dust suction port at its front end,

a dust collecting hose which is connected to the dust collecting partand through which dust is transferred downstream, and

a hose holding part for holding the dust collecting hose while the dustcollecting hose is locked against axial movement,

wherein the hose holding part can be mounted to and removed from theauxiliary handle, so that the dust collecting device can be attached tothe impact tool which is not provided with a mounting part for the dustcollecting device.”

(2)

“The dust collecting device as defined in claim 1, wherein the auxiliaryhandle includes an elongate grip, and an arm extending from the grip ina direction transverse to a longitudinal direction of the grip, andwherein the hose holding part is mounted to the auxiliary handle by aclamping mechanism which is fastened to the auxiliary handle by clampingthe arm from above and below,”

DESCRIPTION OF NUMERALS

-   101 electric hammer (impact tool)-   103 body-   105 housing-   107 barrel-   108 chuck-   109 handgrip (main handle)-   110 side handle (auxiliary handle)-   111 mounting ring-   113 ring component-   115 base-   117 shaft-   119 hammer bit (tool bit)-   119 a bit tip-   119 b shank-   121 grip-   123 arm-   125 extending end portion-   131 through bolt-   131 a head-   133 nut-   135 fastening knob-   137 can-   140 dust collecting device-   141 dust collecting hood (dust collecting part)-   141 a dust suction port-   141 b internal space-   141 through hole-   143 cylindrical sliding member-   144 hose connecting part-   144 a passage-   145 partition-   146 dust collecting hose (dust transfer part)-   146 a bellows-like part-   147 hose holder (hose holding part)-   148 hose holder body-   148 a hose attachment/removal opening-   148 b projection-   149 mounting base-   151 notch-   152 recessed engagement part-   153 clamping mechanism-   154 fixed clamp arm-   154 a clamp face-   154 b clamp part-   154 c arm guide-   155 movable clamp arm-   155 a clamp face-   155 b guide rod-   156 compression coil spring-   157 operation member-   158 screw-   161 hose holder (hose holding part)-   162 hose holder body-   162 a opening-   163 mounting base-   164 locking member-   164 a protruding end-   164 b locking projection-   164 c stopper-   165 pin-   166 compression coil spring-   185 projection-   186 semicircular cylindrical part-   186 a insertion opening-   187 tension member (mounting member)-   188 first rod-like member-   188 a engagement recess    -   189 second rod-like member    -   189 a engagement recess    -   191 compression coil spring (biasing member)    -   193 mounting screw    -   197 band-like member (wrapping member)

1. A dust collecting device that is attached to an impact tool andcollects dust generated by the impact tool which includes a tool bodyand an auxiliary handle removably mounted to the tool body and in whicha tool bit coupled to a front end region of the tool body is caused torectilinearly move in an axial direction of the tool bit, comprising: adust collecting part having a dust suction port at its front end, a dustcollecting hose which is connected to the dust collecting part andthrough which dust is transferred downstream, and a hose holding partfor holding the dust collecting hose, wherein the hose holding part canbe mounted to and removed from the auxiliary handle.
 2. The dustcollecting device as defined in claim 1, wherein the auxiliary handleincludes a ring-like mounting part which can hold the tool body fromoutside, a base formed on the mounting part, a rod-like grip to be heldby a user, and an arm extending from the grip in a direction transverseto a longitudinal direction of the grip and having an extending end, andthe base and the extending end are arranged in parallel to thelongitudinal direction of the grip and clamped by using a bolt extendingtherethrough and a nut threadingly engaged with the bolt, so that themounting part holds the tool body, and wherein the hose holding part ismounted to the tool body together with the auxiliary handle by theclamping with the bolt and the nut.
 3. The dust collecting device asdefined in claim 1, wherein the auxiliary handle includes an elongategrip, and a plurality of opposed anus extending from the grip in adirection transverse to a longitudinal direction of the grip, andwherein the hose holding part is disposed between the opposed arms andincludes a telescopic mounting member which can extend and retract in adirection transverse to the extending direction of the arms, and themounting member is secured to the arms under tension by a biasing forceacting thereon in its extending direction so that the hose holding partis mounted to the auxiliary handle.
 4. A dust collecting device that isattached to an impact tool and collects dust generated by the impacttool in which a tool bit coupled to a front end region of a tool body iscaused to rectilinearly move in an axial direction of the tool bit,comprising: a dust collecting part having a dust suction port throughwhich dust is sucked up, a dust collecting hose which is connected tothe dust collecting part and through which dust is transferreddownstream, and a hose holding part for holding the dust collectinghose, wherein the hose holding part is mounted to the tool body by awrapping member which is detachably wrapped around the tool body.
 5. Animpact tool having the dust collecting device as defined in claim
 1. 6.An impact tool having the dust collecting device as defined in claim 4.